SEOUL, Jan. 30 (Yonhap) -- South Korea's Acting President and Prime Minister Hwang Kyo-ahn held telephone talks with U.S. President Donald Trump on Monday morning for the first time since the latter took office earlier this month, officials here said.

Hwang and Trump were expected to discuss ways to strengthen the bilateral alliance and exchange their views on a series of pending issues, such as North Korea's evolving nuclear and missile programs.

South Korea's Acting President and Prime Minister Hwang Kyo-ahn speaks with U.S. President Donald Trump over the phone at his office in Seoul on Jan. 30, 2017, in this photo, released by the Prime Minister's Office. (Yonhap)

Observers said the two sides were also likely to discuss the planned deployment of a U.S. missile defense system to the Korean Peninsula, which China, along with local liberal politicians, has strenuously opposed.

Hwang has been serving as the acting president since President Park Geun-hye was impeached by parliament over corruption allegations on Dec. 9.

Trump already had a phone conversation with Park on Nov. 10 (Korea time), days after his election victory. During the conversation, the Republican leader said the United States will be "steadfast and strong" in defending against a provocative North Korea.

Alarmed by a series of campaign remarks by Trump that were skeptical of military alliances and trade deals with American allies and partners, Seoul has been trying to maintain close ties with Washington, its top security ally.

Out on the stump, Trump made a host of speeches that questioned the economic value of U.S. security partnerships with allies like South Korea and Japan, and disparaged the South Korea-U.S. free trade agreement as a "job-killing" deal.